No i haven’t checked the control points, how and what am i looking for if i’m looking at the control points?
I have a tried a sweep, but can’t get the orientation of the section curve to stay perpendicular to the rail (stair rail, not sweep rail) @Michael_Pryor
If you are talking about the “Fit Curve” component it didn’t seem to work, though i’m not familiar with that component.
Glad I was able to help. In a simpler situation what I’ve done is to use the two top outside edge curves to make a 2-rail sweep using an arc or part of an ellipse as the sweep curve. For 3D printing it’s necessary to close the bottom of the sweep with a loft or ruled surface between the rails.